Author/Authors :
Parvin، N. نويسنده Amirkabir university of Technology, , , Derakhshandeh Haghighi، R نويسنده Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran. , , Naeimi، M. نويسنده Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran. , , Parastar Namin، R. نويسنده Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran. , , Hadavi، M.M. نويسنده Department of Mining and Metallurgical Engineering, Amirkabir University of Technology, Tehran, Iran. ,
Abstract :
In this research, infiltration behavior of W-Ag composite compacts with Nickel and Cobalt as additives has
been investigated. Nickel and Cobalt were added to Tungsten powder by two distinct methods: mixing elementally and
reduction of salt solution. The coated Tungsten powders were compacted under controlled pressures to make porous
skeleton with 32-37 vol. % porosity. Infiltration process was carried out at 1100 ?C under a reducing atmosphere for
1h. The effect of additives on infiltration of Ag and density were evaluated by SEM and Archimedes methods.
Properties of the specimens were compared following two distinct processes namely: I) sintering simultaneously with
infiltration process and II) sintering prior to infiltration (pre-sintering process). It was found that specimens which
were pre-sintered and then infiltrated with molten silver represent higher hardness and finer microstructure than the
specimens infiltrated simultaneously with sintering.
